[Patent document 1] JP 2008-9703 A
[Patent document 2] WO 2008-075407 A1
There is known a technology to detect an obstacle in a periphery of a vehicle and notify a driver of an existence of the obstacle (see Patent documents 1, 2). Patent document 1 recites calculating of a danger degree of the obstacle to thereby execute a notification operation according to the danger degree. This danger degree is calculated based on a distance to the obstacle, and a kind of the obstacle. In addition, Patent document 2 recites determining of a collision possibility of colliding with the obstacle to thereby output a warning when there is a collision possibility.
Suppose a case where the technology of notifying the driver of the obstacle existence operates in the situation where many obstacles exist in a periphery of the vehicle that is going to turn at an intersection. In such a case, even if the existences of many obstacles are reported, the driver may sense troublesome or, be confused about the existences of too many obstacles.
To that end, the order of the notification relative to the detected obstacles may be determined; thereby, based on the determined order, the existences of the obstacles may be notified. Further, the technology in Patent document 1 may be used for calculating the danger degree depending on the distance to the obstacle, or the kind of obstacle; thereby, the notification may be preferentially made for the obstacle having the higher danger degree. However, the priority of the obstacle which the driver must be careful of is not always correlative to the distance of the obstacle.
In addition, the technology in Patent document 2 may be used for designating the priority in notification based on the collision possibility. However, the priority of the obstacle which the driver must be careful of is not always identical to the order of the collision possibility.